Territory



(No Model.) 3 Sheets-Sheet 1.

F. B. A N. STEAM E INE.

No. 496,966. Patented May 9,1893.

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XOW B (No Model.) 3 Sheets8hee:t 2-. P. B. ALLEN.

STEAM ENGINE. No. 496,966. Patented May 9,,1893.

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INVENTOH ,1 k ITNESS S 3 t e e h s S t e 9 h s 3 5 mm LG N B m B m PS ad 0 M 0 No. 496,966. Patented Ma 9, 1893.

INVENTORI WITNESSES:

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m: nonms PUERS co PNo'ro-umu, WASHINGTON UNITED STATES PATENT ()EFICE.

FRANK. B. ALLEN, OF SALT LAKE CITY, UTAl-I TERRITORY.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 496,966, dated May 9,1893. Application filed October 12, 1891. Serial No. 408,546. (Nomodel.)

To all whom it may concern.-

Be it known that I, FRANK. B. ALLEN, a citizen of the United States,residing at Salt Lake City, in the county of Salt Lake and Territory ofUtah, have invented certain Improvements in Rotary Steam-Engines, ofwhich the follow ing is a specification.

My invention relates to improvements in that class of rotary steamengines wherein the steam is admitted to a series of steam cylindersthrough a central live steam port, said cylinders being arranged in theform of a ring about said steam port with their pistons bearing againstan eccentric annular casing, whereby steam admitted to said cylinders insuccession serves to force said pistons against said casing and thuscause the ring of pistons to rotate, and the object of my invention isto improve the general construction of such engines, whereby the faultsof previous constructions, excessive friction and consequent wear andleakage, are in a great measure obviated.

My invention will be fully described hereinafter and its novel featurescarefully defined in the claims.

In order that my invention may be the better understood, I haveillustrated in the accompanying drawings, a rotary engine of thisgeneral character constructed according to my invention, in Which-Figure 1 is a face or front view of the engine, the cover or face plateof the casing being omitted in order to illustrate the parts behind it.Fig. 2 is a cross section of the engine taken at right angles to Fig. 1and in the plane indicated by line 2-2 in said figure. Fig. 3 is avertical mid-section of the engine taken at right angles to Fig. 2 andin the plane indicated by line 3-3 in said figure. Fig. 4: is a partialcross section taken substantially in the plane indicated by line 4-4 inFig. 3, the outer casing being omitted. Fig. 5 is a longitudinal sectionand end View of the steam cylinder, detached. Figs. 6, 7, 8, 9, 10, 11,12, 13, 1t and 15 are detached detail views which will be hereinafterreferred to.

In the drawings A represents the annular box-like casing of the engine,which casing is provided with a cover section A adapted to be bolted orotherwise secured to the easing A.

B is the steam chest, which is cylindrical in shape and isfixed justabove the center of the casing A, as seen in Fig. 1, so that theirrespective circumferences are eccentric to one another.

0 is the rotating ring member or section carrying the several steamcylinders 0*, of which four are shown in the drawings, although theengine may be provided with any suitable number. a

c are the pistons within the cylinder O each of said cylinders being cutaway at the upper and lower sides as shown in Fig. 5, in order to formguides to guide the piston c in its longitudinal movements.

On each of the pistons c is mounted a pair of wheels or rollers c",which rotate upon shafts c secured to the ends of pistons c. Theperipheries of these rollers bear or roll upon the eccentric innersurface of the annular casing A of the engine, and as the piston isforced out by the pressure of the steam admitted to the cylinder behindit, said wheels will roll down around said eccentric surface, turningthe rotating member or ring section O in the direction of the arrow as,seen in Fig.

1, as will be readily understood.

To the face or cap plate A of the engine casing is secured by means ofbolts or the like, a bent or U shaped casting or tie bar A, againstwhich the steam chest abuts at its exposed end, serving to support saidsteam chest and to counteract the pressure of the steam on the inner endthereof. The supply pipe E, from the steam generator or boiler, passesinto the steam chest B, which it taps at a right angle, where itcommunicates with a passage e, extending lengthwise of said steam chest.The valve D is seated under the inner end of said steam chest and has abore or passage e", co-inciding with the passage 6, which passage is ofthe cross section seen in Figs. 3 and 11, consisting of three connectedbores whereby the valve is adapted to admit steam to the cylinders whenturned to diametrically opposite positions.

cl is the live steam port in the valve D at the upper end of passage 6*,and c, is the port for admitting steam to the cylinder 0*, behind thepiston c, which port is formed partly in the rotating ring section 0,and extends through the rear end of the wall of the cylinder O asillustrated in Fig. 3. The cylinder O receives and exhausts steamthrough the one port 0', as will be hereinafter explained, said portbeing carried around, as the ring section 0 rotates, into coincidencewith the exhaust port at in the valve D, which port communicates througha passage d, with the exhaust outlet in the steam chest B. This passagecl in the steam chest is branched at its lower end into two bentpassages, into the lower straight portions of which branches are fittedslender tubes (1", which abut at their upper ends against spiral springs61" set in the upper ends of the respective branches of passage dwhereby said tubes are kept pressed out with an elastic, yieldingpressure below the level of the lower surface of the steam chest B. Thevalve D is thus held away from the lower surface of the steam chest B,whereby a steam space is maintained between said valve and steam chest,and a tight joint is maintained between the exhaust passages in thesteam chest and valve by means of said springs, thus avoiding any lossof power due to the escape of live steam into the exhaust passage d'.The passage d communicates at its upper end with an exhaust pipe E whichserves to convey the exhaust steam from the steam chest to the outerair.

I will now describe the operation of the engine, referring moreparticularly to the first four figures of the drawings for illustration.

The steam being admitted to the steam chest B from the generator orboiler, and the valve D being open as seen in the drawings, passesthrough said steam chest and valve in the direction of the arrows y inFig. 6, and out through the steam port 61 therein. Entering the cylinderO through the port 0, the steam forces the piston c outward, the wheelsor rollers c on said piston pressing forcibly against the eccentricinner surface of the easing. By reason of the eccentricity of this faceof the casing, the wheels will roll down around said surface, in thedirection of the arrow as in Fig. 1, said rolling movement continuinguntil the widest portion of the space between the casing and steam chestshall have been reached. Before this point has been reached, however,the steam will have been cut off from said cylinder by the passage ofthe port 0', around out of co-incidence with and beyond the live steamport d in the valve, thus allowing time for the expansion of the steamwithin the cylinder, whereby a much greater proportion of its force maybe utilized than where the steam is allowed to entirely fill thecylinder before being out off. By the time the widest portion of thespace between the casing and the ring section will have been reached,the port 0 in the cylinder will have passed around into co-incidencewith the exhaust port in the valve, when the exhaust will begin, saidexhaust continuing for a half rotation of the ring section 0, or untilthe narrowest portion of the space between the easing and ring section,(that at the top in Fig. 1) shall have been reached. By the time theaforesaid cylinder has commenced to exhaust the port 0' of the nextcylinder O in the ring section 0 will have been brought around intoco-incidence with the live steam port d in the valve and steam willenter said cylinder through said port, forcing the piston out andrepeating the operation as before described. Thus it will be seen thatone or more of the cylinders in the ring section is always open to thelive steam.

I will now describe the construction and operation of the valve andsteam chest, referring more particularly to Figs. 6, 7, 8 to 14, whichare details of the steam chest, valve and valve rod, detached.

The steam chest B is cylindrical in form, being as before stated seteccentrically to the peripheries of casing A, and said steam chestprojects out beyond the side of said casing through face plate A", andabuts at its outer end against the bent casting A, which serves as astay to prevent said steam chest from being blown or forced out underthe pressure of the steam.

S is the shaft of the engine which is set securely in the ring sectionon that side opposite the steam chest, and said shaft finds a hearing atG in the casing of the engine. The end of the ring section on the sideopposite to shaft S, is rounded off the main portion thereof beingsquare as seen in Figs. 1 and 3, and said rounded portion finds abearing in the said face plate A wherein it may turn. Between the end ofthe shaft Sand the steam chest B, sets the valve D, normally presseddown against said shaft and away from the steam chest by the springtubes at" d", as will be clearly understood.

D is the valve stem which passes through a longitudinal opening formedfor it through the center of the steam chest and valve, and is providedat its inner end with a square head, D which fits into a correspondingsquare recess in the valve D formed to receive it. On its outer end,beyond the steam chest B, this valve rod is provided with an operatingor reversing lever, whereby it may be turned by reversing the lever,said square head D serving to lock the valve to its rod, as will beclearly understood.

In reversing the engine it is only necessary to give-a half turn to thisreversing lever, when the live steam port in the valve D will be turnedto the position occupied by the exhaust outlet as seen in the drawings.The result of this will be readily observed, the engine will take steamwhen it should exhaust, and consequently will stop.

I do not wish to limit myself to the precise construction andarrangement of the parts as herein shown, as these may be varied to somedegree without departing materially from the principles of my invention.For example it is not essential that the casing A should entirelyinclose the rotating member C, or that such casing shall be a truecircle eccentric to the center of rotation of said rotating member.Indeed, so long as the distance between the periphery or inside surfaceof said casing f romthe center-of rotation gradually increases, the formand extent of said surface is not essential.

Having thus described my invention, I claim- 1. In a rotary engine, thecombination with a ring section carrying the steam cylinders andpistons, of a stationary steam chest about which the ring sectionrotates, and a valve arranged also in the ring section back of the steamchest and independent of the same; substantially as shown and described.

2. In arotary steam engine the combination with a movable ring sectioncarrying steam cylinders and pistons arranged in the cylinders, of astationary steam chest, a valve independent of the steam chest and backof the same, and the valve stem having a polygonal head adapted to fitinto a correspondingly shaped recess in the face of the valve; substantially as shown and described.

3. In a rotary engine the combination with a case, of a ring sectionjournaled eccentrically within the case, said ring section having ports,the steam cylinder arranged on the ring section and also provided withports, the pistons arranged thereon provided with rollers at their outerends, the stationary valve having inlet and exhaust ports, thestationary steam chest having inlet and exhaust passages, and the springpressed tubes arranged in the rear end of the steam chest and adapted tobear against the face of the valve; substantially as and for thepurposes set forth.

4;. In a rotary engine, the combination with the steam chest and thering section mounted rotatively thereon, of the valve D, for governingthe admission of steam to the cylinders on said ring section, said valveprovided with two connected steam passages, equidistant from the valvecenter, whereby a certain degree of elasticity is imparted to saidvalve, as and for the purposes set forth.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

FRANK. B. ALLEN.

Witnesses:

J GEN D. CAPLINGER, LEWIS ScHorPE.

